Railway-signal.



J. S. HOBSON.

RAILWAY SIGNAL.

APPLICATION FILED 0cm. 27. 190B.

Patented July 6, 1909.

2 SHEETS-SHEET 1.

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J. S. HOBSON. RAILWAY SIGNAL.

APPLICATION FILED OUT. 27, 1908.

Patented July 6, 1909.

2 SHEETS-SHEET 2.

UNITED stra'rr s PATENT oniucn.

JOHN S. HOBSON, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO THE UNIONSWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

RAILWAY-SIGNAL.

T 0 all whom it may concern:

Be it known that 1, JOHN S. Honson, a citizen of the United States,residing at Edgewood Park, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inRailway-Signals, of which the following is a specification. 7

My invention relates to air buffers for railway signals and particularlyto the semaphore type of railway signals each blade of which is used togive a plurality of indications, and irrespective if it is movedupwardly or downwardly on its pivot.

I will describe an air buffer embodying my invention and its applicationin a railway signal and then point out the novel features in claims.

In the accompanying drawings in which like reference charactersdesignate similar parts in the respective figures, Figure 1 is avertical sectional view of an air buffer embodying my invention. Figs. 2and 3 are views similar to Fig. 1 but showing the parts in differentpositions. Figs. 4, 5 and 6 are views, partly in section and partly inelevation, showing a semaphore signal in three diiferent positions andan air buffer embodying my invention in its three differentcorresponding positions. In these figures certain details ofconstruction are omitted.

Referring now to the drawings and par ticularly to Figs. 4, 5 and 6, thesemaphore blade is designated by 10 and the spectacle 1 1. If the bladeis moved from its horizontal position downwardly on its pivot to itsinclined and vertical positions, the spectacle is made sufficientlyheavy to always tend to move the blade to its horizontal position. If onthe other hand the blade is moved from its horizontal position upwardlyon its pivot to its inclined and vertical positions, the weight of theblade and spectacle are both ern loyed to return the blade to thehorizonttl position. Both of these arrangements are well understood inthe art, and my invention is applicable to either. The spectacle andblade are suitably fastened together and they are provided with a shaft12 which is suitably journaled, and arm 18 is provided, generally on theshaft 12, to which is connected the up and down rod 15 through which theblade is moved from its horizontal to its inclined and verticalpositions. The up and down Specification of Letters Patent.

Application filed October 27, 1908.

Patented July 6, 1909.

Serial No. 459,709.

1 rod 15 may derive its longitudinal movements from any desired type ofmotor. Its downward longitudinal movement may in some cases be obtainedby its own weight and that of the parts connected to it when the rod isreleased from the position to which it has been moved, or its downwardmovement may be obtained through the motor, in which case in automaticsignals its upward movement is under the influence of the counterweightof the signal. In the drawings I have shown the rod 1 5 connected withwhat is known in the art as a slot arm 16, which as usual is pivoted atone end, and provided with levers and electro-magnets by means of whichits pivoted lever 16 may be held rigid and engage projections on a chaindriven by a motor and thereby move the rod 15 upward. An illustration ofthis arrangement of parts is disclosed in United States Patent N 0.611,943 granted October 1, 1898, upon an invention of J. G. Schreuder.The downward movement of the rod 15 is cushioned to prevent shock and abuffer is employed for this purpose. My invention relates particularlyto the buffer, which is an air buffer and preferred forms thereof willnow be described.

Figs. 1 to 6 illustrate one form which my invention may assume, and aswill be seen, it comprises telescoping parts which are adapted to havesuccessive movements according to the movements of the blade 10.

Referring now particularly to Figs. 1, 2 and 3, 19 designates a partwhich serves as a piston, that is, it comprises a piston head 19 and ahollow rod portion 19", the lower end of which is adapted to bepivotally secured as at 20 to any suitable support, for example theframework supporting the signal operating mechanism. At or near the head19'" is an annular groove 19" or there may be two oppositely arrangedrecesses or cut-outs, which coact with a locking device to behereinafter described. 21 designates a second piston comprising a head21 and a hollow rod 21 which slides in the hollow rod portion 19 of thepiston 19. The end of the rod 21 is preferably provided with a packingring. At or near the end of the rod 21 oppositely arranged openings 21are provided in which are placed balls 22 having a diameter larger thanthe thickness of the Wall of the rod 21 23 designates a cylinder whichis suitably The cylinder which receives the heads 19 21 has connectedwith it a rod 23 which projects into the rod 19 and is movable.

therein. The rod 23 is provided at its lower end with a packing ring orrings and intermediate its length with annular groove 23 or there may betwo oppositely arranged openings which coact with the balls 22. Theballs 22 and the annular grooves 19 and 23 or oppositely arrangedrecesses as the case may be constitute a locking device by means ofwhich the several parts of the air buffer may be moved successively.This perhaps will be better understood from a description of theoperation of the device.

When the signal 10: is in its horizontal position indicating dangerorstop the parts of the air buffer are in the position shown in Figs. 3and 6. If now the signal blade 10 is moved from its horizontal posi tionto its inclined position (see Fig. 5-) the slot arm carries with it thecylinder 23-, and piston 21, the cylinder and piston 21 being connectedor locked together by the balls 22 which extend or project into theannular groove 23 When the blade 10 reaches its final inclined positionthe parts are in the position shown in Figs. 5 and 2. In the event thatthe blade 10 is returned to its horizontal position the cylinder 23 andpiston 2-1 will move to the position shown in- Figs. 3 and 6. If,however, the blade is moved to its vertical position (see Fig. 4), themovement of the cylinder 23 with the slot arm 16 through the rod 23causes the balls 22 to enter the annular recess 21 thus connecting orlocking the pistons 19 and 21 together and leaving the cylinder 23 freeto move independently of the istons 19 and 2-1 after the blade has movecto its vertical position. The parts will then be the positions shownFigs. 1 and 4. If the blade 10 is moved again to its inclined position,the cylinder 23 will return to the position shown in Figs. 2 and 5,which willbring the annular groove 23 opposite the balls 22- so that inthe event of the blade 10 being moved to its horizontal position thecylinder 23 and piston 21 will be free to move to the position shown inFigs. 3. and 6. It will be seen that the pistons 19 and 21 will belocked by the balls 22 during the movement of the cylinder 23 with theblade 10- from its vertical to its inclined position.

It will be understood, of course, that the blade and the up-and-down rodare suitably supported against downward movement by suitable. devicescomprised in the signal op? erating mechanism except, of course, at suchtimes as desired that the blade shall give different indications, andthat the buliter mechanism embodying my invention is for the purpose ofcushioning the downward movement of the up-and-down rod 15 and partsconnected therewith.

It is, of course, necessary to provide valves which will open freely forthe admission of air during the upward movement of the cylinders, andalso to provide valves which will permit the air to escape slowly duringthe downward movement of the cylinders. These valves may be of anysuitable or well known construction. As shown I form a pocket 32 in thepiston 21, which is pro-. vided with a seat for a ball valve 33. Asimilar pocket 34 is provided in the head of the cylinder 19. which alsohas a seat for a ball valve 35. These valves will open freely to admitair when the cylinders are moved upwardly but will close under thepressure of air within the cylinders when the latter move downwardly.Strips of metal 36 project over the pockets. to prevent the balls beingforced out of them.

38 designates an adjustable air vent provided in the cylinder 23.

aving thus described my invention, what I claim as new is: i

1. The combination with a signal blade, of means for moving it to. aplurality of positions of indication, and an air butter for cushioningthe blade in its movements, said air buffer comprising two pistons and acylinder.

2. The combination with a signal blade, of means for moving it to aplurality of positions of indication, and an air buller for cushioningthe blade in its movements, said air buiter comprising a piston having ahollow rod, a second piston also having a hollow rod which moves in thehollow rod of the first piston, and a cylinder having a rod which movesin the hollow rods of both piss tons.

3. The combination with a signal blade, of means for moving it to aplurality of posi tions of indication, and an air buffer for cushioningthe blade in its movements, said bulier comprising two pistons and acylinder which have telescoping parts, and means for locking thecylinder with one of the pistons or the two pistons together in thesuccessive movements of the blade.

4. The combination with a signal blade, of means for moving it tov aplurality of positions of indication, and an air buffer for cushioningthe blade in its. movements, said buffer comprising two. pistons and acylinder which have telescoping parts, and means for loo-king thecylinder with one of the pistons or the two. pistons together in thesuccessive movements of the blade, said means being operated andreleased by the movement of the parts of the air buffer.

5. The combination with a signal blade; of a cylinder connectedtherewith; a rod 23 connected therewith; a piston 21 on which saidcylinder moves; a hollow rod 21 for said piston through which said rod23 extends; a fixed piston 19 on which said cylinder also moves; ahollow rod 19 into which the rods 23 and 21 extend; and means for attimes holding the piston 21 immovable, relatively, to the piston 19; andother means for at times holding the iston 21 immovable relatively tothe cylinc er 23.

6. The combination with a signal blade, of air buffer for cushioning theblade in some of its movements; said bufi'er comprising a cylinder andtwo pistons which have telescoping parts; a connection between thecylinder and blade and a connection between one of the pistons and afixed part; and means for locking the cylinder with one of the pistons,or the two pistons together in the successive movements of the blade,said means being operated and released by the movements of the parts ofthe air buffer.

7. The combination with a signal blade, an air bufi'er for cushioningsaid signal blade in some of its movements; said air bufi'er comprisinga cylinder connected with the signal blade, a rod carried by saidcylinder and having an annular recess, a piston on which said cylindermoves, a hollow rod for said piston having an annular opening, a secondpiston on which said cylinder also moves connected with a fixed supportand having an annular recess; and balls arranged in the annular openingof the hollow stem of the first piston, said balls coacting with thesaid recesses to lock together and release by movements of the blade,the cylinder with one of the pistons or the two pistons.

8. The combination with a signal blade, an air buffer for cushioningsaid signal blade in some of its movements; said air bufi'er comprisinga cylinder connected with the signal blade, a rod carried by saidcylinder and havin an annular recess, a piston on which said cylindermoves, a hollow rod for said piston into which said rod extends and saidhollow rod having an annular opening, a second piston on which saidcylinder also moves, said second cylinder being connected with a fixedsupport and having an annular recess, a hollow stem for the secondpiston in which said rod and the hollow rod of the first piston extends;and balls arranged in the annular opening of the hollow stem of thefirst piston, said balls coacting with the said recesses to locktogether and release by movements of the blade, the cylinder with one ofthe pistons or the two pistons.

In testimony whereof I have signed my name to this s ecification in thepresence of two subscriber witnesses.

JOHN S. HOBSON.

Witnesses:

O. C. WHITE, JAMES CHALMERS. Jr.

